Add some of the `alive_bar` methods to `bar`

[shepster]

This is a feature request.

There are times when I want to display information about the progress while it is happening but then omit it in the end. Often when I am exiting with alive_bar() as bar: I set bar.title for a final message. However I always get the elapsed, monitor, and stats that were set by alive_bar() at the start.

I would very much like to be able to set bar.[elapsed_end|monitor_end|stats_end] (e.g. bar.elapsed_end=False) in the middle/end of an alive_bar() progression.

[rsalmei]

I don't quite get it, you can set elapsed_end=False right at the start using with alive_bar(elapsed_end=False).
Why would you want to set it after you instantiated the bar?

[shepster]

There have been a couple of times I've wanted this. Usually during a failure condition. Let's say I'm starting up a database and I'm waiting for it to become available. Knowing how long it takes for the database to start is a useful diagnostic issue. Did it take 5 minutes? Did it take 15? Having the elapsed_end=True is desired in that case. However, if the database failed to start, I don't need to know how long it took to fail. I can catch this failure, set the title to reflect the failure, but I can't turn the elapsed_end off.

This is a wonderful library and you've put a lot of work into it. Thank you! Since you can do things like change the title it seemed like an oversight to not be able to change the elapsed_end. However, as a programmer I can understand that if you add the elapsed_end parameter to bar, why not add all the parameters of alive_bar to bar? Sometimes it is better to keep the design in check rather than allow the code creep of every user's whim.